Parser stalls indefinitely for certain input files

[dschwen]

Description of the enhancement or error report

Open and closing tags in variable blocks (possibly elsewhere, too) cause the parser to stall (possibly run into an infinite loop).

Rationale for the enhancement or information for reproducing the error

Minimal input to reproduce the bug:

[Variables]
  [./a][../]
[]

Identified impact

Bad behavior. Malformed input should not cause the code to stall indefinitely.

[permcody]

@rwcarlsen - will your parser handle this case?

[dschwen]

For full backward compatibility it should go into an infinite loop, too.

[rwcarlsen]

Moose (c++) parser or the python one? Also, does it loop forever in other blocks (not just Variable)? And does it still break if the closing tag is on a separate line? The new parser works.

[dschwen]

The old C++ parser is the one that locks up. The new parser will have a common C++/python (cython) code base, right?

It does not lock up if the block closing tag is on a separate line.

[rwcarlsen]

New parser (mostly) doesn't care about whitespace. You will soon be able to have one-line input files!

We haven't fully decided if we prefer python bindings to the new c++ parser or just to have a separate but similarly architected new python parser (which I have already written) with a shared set of tests between the two.

[dschwen]

You will soon be able to have one-line input files!

Will we have an Obfuscated MOOSE Contest as well?